A. Motor-generator set
B. Motor converter
C. Rotary converter
D. Mercury arc rectifier
A. low power factor
B. high power factor
C. zero power factor
D. none of the above
A rotary converter operates at a______________? Read More »
Rectifiers and Converters A. d.c. only
B. a.c. only
C. partly a.c. and partly d.c.
In a rotary converter armature currents are______________? Read More »
Rectifiers and Converters A. Illumination
B. Electrolysis
C. Variable speed operation
D. Traction
In which of the following appUcations, direct current is absolutely essential ? Read More »
Rectifiers and Converters A. anode
B. cathode
C. shell bottom
D. mercury pool
In a mercury arc rectifier positive ions are attracted towards______________? Read More »
Rectifiers and Converters A. Telephones
B. Relays
C. Time switches
D. All of the above
In which of the following equipment direct current is needed ? Read More »
Rectifiers and Converters A. Synchronous motor
B. Squirrel cage induction motor
C. Slip ring induction motor
D. Any of the above
Which of the following AC. motors is usually used in large motor-generator sets? Read More »
Rectifiers and Converters A. same
B. less
C. double
D. three times
A. 0.05 V to 0.2 V per cm length of the arc
B. 0.5 V to 1.5 V per cm length of the arc
C. 2 V to 3.5 V per cm length of the arc
D. none of the above
The potential drop in the arc, in a mercury arc rectifier, varies_____________? Read More »
Rectifiers and Converters A. its ionization potential is relatively low
B. its atomic weight is quite high
C. its boiling point and specific heat are low
D. it remains in liquid state at ordi¬nary temperature
E. all of the above
Mercury, in arc rectifiers, is chosen for cathode because________________? Read More »
Rectifiers and Converters